Introduction

Tympanic membrane (TM) retraction refers to the inward movement of the TM from its usual location. This condition is marked by partial collapse of the middle ear spaces, affecting either the Pars Tensa (PT) or Pars Flaccida (PF) of the tympanic membrane.[1] Previously benign retractions can become active over time, and larger retractions may accumulate migrating epithelium. This accumulation can lead to the formation of a cholesteatoma, which may erode the ossicular chain or disrupt the middle ear, ultimately resulting in hearing loss. Otoscopic evidence of tympanic membrane retractions is often regarded as an indicator of disease progression and a marker of its severity.[2] Therefore correct diagnosis and management with regular follow up of TM retraction pockets is essential.

Eustachian tube dysfunction and weakening of the tympanic membrane from otitis media with effusion are the two major contributors to pathophysiology of retraction pockets.[3] The point prevalence of PF and PT retraction in children aged 5 to 16 years is reported to range from 14% to 26% for PF retractions and from 0.3% to 3.7% for PT retractions.[4] The four stage classification of Sade for pars tensa retraction [5] and the four stage classification of Tos et al for pars flaccida retraction [6] are currently clinically most accepted classifications irrespective of age and presence or absence of OME, although some researchers have questioned the clinical usefulness of these classifications.[7,8] In Adults, retractions are seen in inactive squamous chronic otitis media (COM) and hearing impairment is often the only presentation.[9]

Otoscopy and tympanometry are complementary tests that provide distinct yet valuable clinical insights regarding tympanic membrane retractions. Otoscopy provides a visual assessment of the tympanic membrane's appearance, while tympanometry measures the mobility of the tympanic membrane and middle ear function. Together, these tests help in assessing the presence, severity, and impact of retractions on ear health. Oto-endoscopy allows better visualization of TM because of closer positioning and better illumination and found significantly better than tympanometry. It is time efficient, can be used for uncooperative patients and patients with a narrow ear canal.[10] Otoendoscopy has gained significant popularity in recent years for both diagnostic and surgical purposes.[11,12]

Compared to traditional microscopic techniques, otoendoscopy offers several advantages, including a wider and magnified field of view, improved illumination, and the ability to visualize the ear canal and tympanic membrane from various angles. This enhanced perspective allows for more detailed examination and more precise surgical interventions, ultimately improving patient outcomes. Additionally, otoendoscopy serves as an exceptional teaching tool due to its detailed and dynamic imaging capabilities.[13.14] Recently, several technical enhancements have been introduced to otoendoscopy beyond standard white light (WL) endoscopy, primarily through the use of specific optical filters. For instance, the Spectra A filter reduces red hues, improving the contrast and visibility of structures by minimizing the interference from red tones. On the other hand, the Spectra B filter enhances the green and blue spectral components, which can aid in distinguishing subtle details and variations in tissue color that may be critical for accurate diagnosis and surgical precision. These advancements allow for better visualization and assessment of ear conditions.[15]

After an exhaustive review of the available print and electronic literature it was found that there have been similar studies internationally but very limited in the Indian scenario. Hence a cross sectional descriptive study was designed with the aim to clinically evaluate and grade tympanic membrane retraction and to compare otoscopy and otoendoscopy findings in different grades of tympanic membrane retraction.

Materials and Methods

The study was conducted in the Department of a tertiary care teaching institute over a period of one year. The patients attending for otorhinolaryngology services of the institute, diagnosed as cases of TM retractions were included in this study after a written and informed consent statement from patient and parent or legally authorized representative in case of minor’s participant. The study was started after the approval of the protocol by the Institutional Ethics Committee (XXXX/ETHIC/ decision number:94).

Patients with age group below 6 years, TM perforation, history of ear surgery, COM with complications and any psychiatric disorder were excluded. Each patient selected for the study underwent a thorough medical history review and a comprehensive ear, nose, and throat examination. Each of these patients were graded clinically according to the Sade and Tos system of classification for pars tensa and pars flaccida retractions respectively using pneumatic otoscope and otoendoscope.

Statistical testing was performed using the Statistical Package for the Social Sciences (SPSS) version 17. Continuous variables are reported as mean ± standard deviation (SD), while categorical variables are presented as absolute numbers and percentages. Before statistical analysis, data were assessed for normality to ensure appropriate analytical methods were applied. The Kruskal-Wallis test was used for initial comparisons among multiple groups, followed by paired comparisons with the Mann-Whitney U test to evaluate differences between specific groups. Categorical variables were analyzed using the chi-square test. A p-value of less than 0.05 was considered statistically significant for all tests.

Results

A total of 5,076 patients who visited the otorhinolaryngology department for otological services out of which 111 patients of tympanic membrane retraction were included in this study. Of 10,152 ears that were evaluated TM retractions were found in 190 ears, an incidence rate of 0.018 in our study group. 79 (71.2%) patients had bilateral ear pathology whereas 32 (28.8%) patients had unilateral pathology making a total of 190 ears of 111 patients.

The median age was found to be 32 years with a minimum-maximum age ranging from 7-70 years with mean age of 32.45 years ± 15.20 years. 54 (48.6%) out of 111 patients were in the age group 21-40 years. Study comprised of 48 (43.2%) females and 63 (56.8%) males with the male-to-female ratio was 1.3:1. Patients belonging to urban areas were 57 (51.4%) as compared to 54 (48.6%) from rural areas.

Aural fullness was the commonest symptom 127 (66.8%) of the 190 ears followed by hearing loss in 108 (56.8%) ears. Retractions were coincidentally found in 20 (10.5%) ears with no aural symptoms. History of progressive hearing loss was present in 68 (62.9%) out 108 ears with hearing loss. The duration of hearing loss in our cases was less than or equal to 1 month in 34 (32.7%) ears, less than 1 year in 68 (63.6%) ears. On examination of 190 ears, isolated PT retraction (Figure- 1,2,3) was found in 109 (57.3%) ears, isolated PF retraction (Figure-4) seen in only 4 (2.1%) ears with the remaining 77 (40.5%) ears having both PT and PF tympanic membrane retractions.

Figure 1: Right ear: Grade II PT retraction	Figure 2: Right ear: Grade III PT retraction
Figure 3: Left ear: Grade IV PT retraction	Figure 4: Right ear: Grade IV PF retraction

In total 186 (97.89%) of the 190 ears had PT retraction and 81 (42.6%) ears had PF retraction. The distribution of pars tensa retractions on otoscopic examination,there was no retraction, i.e., a normal (Grade 0) PT in 6 (3.2%) of the ears, 110 (57.9 %) ears had Grade I retraction, 27 (14.2%) ears had Grade II retraction, Grade III retraction was seen in 20 (10.5%) ears with 27 (14.2%) ears showing Grade IV retraction. Compared to this on Otoendoscopy 4 (2.1%) ears had a normal PT, 105 (55.3%) ears had Grade I, 29 (15.3%) ears with Grade II retraction, 23 (12.1%) ears had Grade III retractions and Grade IV retractions were seen in 29 (15.3%) ears. (Figure-5) A cross-tabulation of these findings revealed a significant relationship (p<0.001) between otoscopy and otoendoscopy. A difference in findings was seen in 23 (12.1%) ears between otoscopy and otoendoscopy.

Figure-5: Distribution PT Grade on Otoscopy and Otoendoscopy	Figure-6: Distribution PF Grade on Otoscopy and Otoendoscopy

The distribution of PF retractions on otoscopic examination there was no retraction, i.e., a normal (Grade 0) PF in 121 (63.7%) of the ears, 28 (14.7%) ears had Grade I retraction, 25 (13.2%) ears had Grade II retraction, Grade III retraction was seen in 13 (6.8%) ears with only 3 (1.6%) ears showing Grade IV retraction. Compared to this, 109 (57.4%) ears had a normal PF on otoendoscopy, 30 (15.8%) ears had Grade I, 28 (14.7%) ears with Grade II retraction, 16 (8.4%) ears had Grade III retractions and Grade IV retractions were seen in 7 (3.7%) ears (Figure-6). A cross-tabulation of these findings demonstrated a significant relationship (p<0.001) between otoscopy and otoendoscopy. Additionally, a cross-tabulation of otoendoscopy findings revealed a significant relationship (p<0.001) between PT and PF retractions.

Discussion

A total of 111 patients of tympanic membrane retraction were included in this study. 79 (71.2%) patients had bilateral ear pathology whereas 32 (28.8%) patients had unilateral pathology making a total of 190 ears. In our study of 111 patients the median age was found to be 32 years and 54 (48.6%) patients in the age group 21-40 years. This preponderance in young adults was also reported by Grewal et al.[16 ] We found no substantial gender predisposition with a male-to-female ratio was 1.3:1. Aural fullness was the commonest feature in 127 (66.8%) ears. Otalgia was present in 35 (18.4%) ears and tinnitus in 30 (15.8%) ears with 10% being asymptomatic ears. History was less than 1 year in 63.6% ears. A study reported mean length of history of hearing problem in 1267 children to be 13 months (SD=7.1).[2] Most children possibly had longer fluctuating hearing loss that was undetected.[1]

Mills in their study stressed that despite few symptoms and incidental detection, retraction pocket require regular follow up to 3 months, since they do have propensity to progress to cholesteatoma and cause ossicular erosion and significant hearing loss.[17] Borgstein et al emphasized the need for re-examination for every 3 months for many years children tend do show more aggressive course, as do ears with higher degree of retraction at the time of initial detection.[7] Given the need for follow up of staging is required, a reliable staging system is needed to ensure intra and inter observer reliability.

Bilateral ear pathology was seen in 79 (71.2%) patients perhaps because 54 out 111 patients were from a rural background with a consequent delay and inadequate treatment of childhood OME. Childhood OME is often initiating factor and retractions are known to sometimes remain and progress after the resolution of OME.[1] Additionally factors like ET cartilage defects, Patulous ET (significant in adults and adolescents), atopy and reflux, have been postulated. We observed the TM by both otoscopy and otoendoscopy and sought to compare the clinical findings of TM colour, transparency, mobility and retraction grade. A difference in staging between otoscopy and otoendoscopy was seen in 23 (12.1%) ears of PT retractions and 29 (15.3%) ears of PF retractions. A cross-tabulation of these findings revealed a significant relationship (p<0.001) between otoscopy and otoendoscopy.

A close association was observed between otoscopy and otoendoscopy (p<0.001) for both PT and PF. We statistically analyzed the results with a view of exploring whether there was a significant association between otoscopic and otoendoscopic results. One of the aims of our study was to establish if otoendoscopy was superior to otoscopy and whether there was a need for further investigation like microscopy in case where there was any significant discrepancy in any particular grade of the disease. Our p values suggest a significant correlation exists. An-Suey et al. found that pneumatic otoscopy failed in 2.5% (5/201) of cases. The failures were attributed to factors such as the narrowness of the external ear canals and the presence of relatively long internal hairs.[10]

Videotelescopy and tympanometry accurately predicted myringotomy outcomes in cases where pneumatic otoscopy failed. However, due to the limited number of failures in the study, further research is needed to determine whether videotelescopy or tympanometry is significantly superior to pneumatic otoscopy.[10,18] Cross-tabulating otoendoscopy findings revealed a significant relationship (p <0.001) between PF and PT retraction. In our study, 77 (95.1%) ears of the patients with PF retractions also had involvement of PT which was higher than 78% quoted by Tos.[6] It was also seen that 109 (57.36%) of 186 ears with PT retraction had a normal PF in contrast to the close correlation between changes in PT and PF reported by Sade, especially in ears in which effect of prolonged low pressure on PT dominates.[19] We found combined PT and PF retractions in 77 ears (40.53%). This contrasts with another study that reported a higher prevalence of retractions in either PT or PF alone, rather than both simultaneously.[2 ]Current study conducted in age group7-70 years showed PF retraction in 81 (42.6 %) ears, PF retractions are more common in adults than in children. Borgstein reported PF retraction in only 4% of ears in his pediatric series which is also corroborated by Bluestone and Klein.[20. 21]

Limitations of our study was we did not study the etiology of retractions in our study. We were also unable to carry out eustachian tube function tests and myringotomy in these patients which would have aided in establishing the possible etiology and comparing the sensitivity and specificity of otoscopy and otoendoscopy.

Conclusion

It was thus concluded that detailed examination using both otoscope and otoendoscope is quintessential for early detection and classification of tympanic membrane retractions. Otoscopy and otoendoscopy are useful aids for evaluating and monitoring the clinical profile of TM retractions. The key advantage of the videotelescopy used in this study is its real-time magnification and clarity of the eardrum image, which is displayed on a monitor. This enhanced visualization allows for more accurate assessment and diagnosis compared to traditional methods.  The acquisition of large, clear, high-quality images enables precise evaluation and documentation of ear structures, facilitating accurate diagnosis and effective treatment planning. The technique can be seamlessly applied in clinical practice, research, instructional settings, and medical trainee supervision. An added benefit is that the visual display can be shared in real-time with colleagues or students, enhancing collaborative learning and immediate feedback. Additionally, computer manipulation with image-processing software allows for digitized archiving, enabling future analysis and facilitating the monitoring of retraction pockets over time. These significant benefits position otoendoscopy as a potential gold standard for examining tympanic membrane (TM) retractions in outpatient settings, particularly in referral institutes where such facilities are readily available.

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